Oops, it doesn't look like 'parks for free this day' is a national day..

Other days

unicorn

Unicorn Day
get funky

Get Funky Day
kiss a ginger

Kiss A Ginger Day
one

One Day
hoodie

Hoodie Day
first love

First Love Day
stud

Stud Day
ruby

Ruby Day
self care

Self Care Day
bounce

Bounce Day